SAN FRANCISCO -- The Bush administration got a mostly cool reception when it went before a federal appeals court Monday to extend its victory over state medical marijuana laws by cracking down on doctors who recommend pot.

"Why in this world does an administration that's committed to federalism want to go to this length to put doctors in jail for doing things that are perfectly legal under state law?" asked Judge Alex Kozinski of Pasadena, one of the three members of the 9th U.S. Circuit Court of Appeals assigned to rule on the government's appeal.

A conservative with a passion for the First Amendment, Kozinski dominated the hourlong hearing, recalling Supreme Court precedents helpful to the doctors' point of view, sending his appreciation to four "very brave" patients who signed onto a supporting brief, suggesting to a lawyer who was having trouble fielding a practical question: "Why don't you look at the NORML (National Organization for the Reform of Marijuana Laws) Web site?"

Since passage of Proposition 215, the 1996 California medical marijuana initiative, the government -- first under President Clinton and now under President Bush -- has sought to prosecute doctors who recommend marijuana to their patients, drop them from the federal Medicare and Medicaid programs or revoke their licenses to prescribe drugs.

A patient's right to use marijuana under the initiative is triggered by a doctor's recommendation. The federal government contends the recommendation, therefore, amounts to aiding and abetting illegal conduct -- the acquisition of a drug that's banned for all purposes under the federal Controlled Substances Act.

Judges so far have rejected the argument, agreeing with the American Civil Liberties Union and a large group of medical and health organizations that contend the threatened sanctions interfere with legal speech, not illegal activity, in violation of the First Amendment.

Injunctions issued by federal trial judges in San Francisco have blocked any crackdown.

Last May, however, the U.S. Supreme Court ruled in favor of the government in a separate case against medical marijuana patients and dispensaries under Proposition 215. The appeal of the injunction in the doctors' case was waiting in the wings.

When the 9th Circuit took it up Monday, Judge Betty Fletcher of Seattle joined Kozinski in probing soft spots in the administration's position.

Her focus: the government's apparent difficulty in defining the types of statements that would get a doctor in trouble.

Fletcher posed a series of questions about a hypothetical conversation between a doctor and a cancer patient who's unable to eat because of the side effects of chemotherapy.

Mark Stern, the government's lawyer, said the doctor could tell the patient that marijuana was the right treatment but would have to add that it's illegal and that the advice shouldn't be taken as a recommendation to use the drug but that the doctor could try to get the patient into a federally approved program.

Kozinski compared that answer to the fine print on the back of a credit card statement.

Only the third member of the 9th Circuit panel, Chief Judge Mary Schroeder of Phoenix, asked questions that seemed sympathetic to the government.

She asked the ACLU's lawyer, Graham Boyd, whether a doctor had a right to issue "scrip that could be turned into marijuana" -- a written statement that could be taken to a marijuana distribution center to obtain the drug, interfering with the federal government's interest in controlling it.

She also suggested sending the case back to the federal trial court for further examination in light of the Supreme Court's 2001 Proposition 215 ruling.